American actor Megan Mullally, 58, is best known for playing boozy, pill-popping, sarcastic socialite Karen in Will & Grace – the hit sitcom that ran from 1998 to 2006 and is set to make a comeback. She received seven consecutive Emmy nominations for the role, winning twice. Also an accomplished dancer and singer, Mullally has starred in Broadway musicals and recently formed a band called Nancy and Beth. She is married to comedy actor Nick Offerman (AKA Ron Swanson from Parks and Recreation).

You’re coming to the UK with your band, Nancy and Beth. Looking forward to the gigs?I’m so excited. Ever since we started this band, I’ve been fixated on the idea that you’ll respond to it really well in the UK. You Brits will get our wry wit, I think. It’s all-singing, all-dancing, all-entertaining, kind of punk vaudeville. There’s a touch of Vegas in there, some emo-folk and blues, some dirty rapping. And some clean rapping. But mainly dirty.

What can we expect between songs?Live sex acts. Between the band but also with lucky audience members. We’ll run a raffle. The thing is, nobody knows I even sing, apart from my mom and a few people on Broadway. People find it confusing I’m in a band, even though music was my main thing before acting. There’s kind of a double standard: if a musician decides they want to act, everybody falls over themselves. But if you’re an actor and you have a band, everyone’s “Ugh, disgusting! It’s a vanity project.”

It’s crazy. Why can’t I ever play a nice, normal, salt-of-the-earth type? Is there something I should know?

How did you get together with your bandmate, Stephanie Hunt?We met doing an indie movie in Texas and hit it off. Steph said: “I write songs and play the ukulele”. I was like, “Oh really, little girl?” But she busted out the ukulele, made me sing along and our voices just harmonised really well. At that moment, the world changed. There’s a 30-year age gap between us but it’s the darnedest thing. We’re best friends. She’s like family. It’s the same kind of psychic connection that Sean Hayes and I have as Jack and Karen in Will & Grace. A strange chemistry.

Talking of Will & Grace, what can you tell us about the reunion series?I’m so excited about it. We start shooting in August so I’m considering it my vacation. NBC are saying it’s going to be a one-time special thing, just 10 episodes. But if it goes well, there might be more.

What was it like when you and your co-stars met up again?The weirdest thing is how not weird it is. It’s been 11 years but we all just picked up right where we left off. It was like we’d been away for the weekend and come back on a Monday.

What do you think your character has been doing for the last 11 years?Besides getting up to no good? Alcohol might not be making much of a dent any more. She may have graduated to crystal meth. Karen was always such a lawless rebel: carrying a gun in her purse, flirting with 14-year-old boys. She’s the worst. You know that horrible guy Milo Yiannopoulos? She has about as many redeeming qualities as he has.

The political landscape has changed since the show was last on air, notably with your new president. Will the new series reflect that?How could it not? The main goal is to be funny, first and foremost, but the writers are so smart, they’ll find ways to comment on what’s going on in the world. The show was never overtly politicised, it was just topical. We didn’t hammer home that Will and Jack were gay – they just were gay, among other things. Viewers enjoyed it as entertainment, but maybe some teeny part of it got a little toehold in the backs of their minds and some change grew out of that.

Well, as former vice-president Joe Biden said: “Will & Grace did more to educate the American public on LGBT issues than almost anything anybody has ever done.”Oh my God, we all just about dropped dead when he said that. It was such a thrill and privilege.

Is it true that when Madonna guest starred in 2003, she called you all by your character names?Not me, just the others. She knew mine, because she’d requested that all her scenes were with Karen. Some people seemed outraged that she didn’t know the cast’s names but hey, she’s Madonna. She was there with no entourage, doing an episode of our show, which was a big deal. I wouldn’t have cared if she’d called me Bob. She was really cool – super-professional, a perfectionist but also very open. She told me all sorts of scurrilous stories.

You’ve won two Emmys and four Screen Actors Guild awards. Where do you keep them?I hate to say this. They’re all in a closet. But it’s a lovely closet and they’re arranged very respectfully. I value them greatly, I just don’t put them out for people to admire. I think that’s kind of yucky.

You’re known for slightly unhinged characters… I know, it’s crazy. Why can’t I ever play a nice, normal, salt-of-the-earth type? Is there something I should know? It’s fun to play villains and character roles, of course – but I’m sure it’s also fun to be a really big star and play the lead in everything, where all you have to do is show up and not blink.

You and your husband, Nick Offerman, have been called “the Jay Z and Beyoncé of comedy”.That’s hysterical but I’ll take it. I guess I’m the rapper, so I might be the Jay Z. Although Nick can bust a rhyme with the best of them. If he’s Beyoncé, I don’t think we’re ready for his jelly.

Is it true you vowed never to go a fortnight without seeing each other?Yes and it’s worked for 17 years. It makes a huge difference. We’re always shooting something or away on tour, but we put our relationship first, even if it means flying in to see each other for the weekend. Nick tends to bear the brunt of the commutes because he’s so hardy. What a man. He’s a keeper.

He’s a master woodworker, too. Does he whittle you little gifts?He’s whittled me gifts of all sizes, from big pieces of furniture to little trinkets. The beautiful box that my engagement ring was in when he proposed was something Nick carved out of wood. He proposed in London, actually – in Queen Mary’s rose garden in Regent’s Park, on the Japanese footbridge. It was spring and the ducks were swimming in pairs. Mating season. That’s another reason why we have a special affection for the UK.

Nick’s forever changing his facial hair, with moustaches and beards. What’s your favourite?Who can keep up? He’s had every configuration. At one point, he was doing a movie that meant he had a white mohawk that wrapped around into a chinstrap beard. And I had to have sex with him. Tough gig.